Hung-Chou Kuo

Increased exhaled nitric oxide in active pulmonary tuberculosis due to inducible NO synthase upregulation in alveolar macrophages

Nitric oxide (NO) plays an important role in resistance to Mycobacterium tuberculosis infection. Our aim was to determine whether inducible NO synthase (iNOS) expression and generation of reactive nitrogen intermediates (RNI) by alveolar macrophages (AM) are increased in patients infected with M. tuberculosis. NO levels in the exhaled air of 19 active pulmonary tuberculosis (TB) and 14 control subjects were measured using a chemiluminescence NO analyser. The expression of iNOS on AM was studied by labelling AM with anti-mac iNOS polyclonal antibody analysed with a flow cytometer. The spontaneous generation of RNI by cultured AM was also measured. Data are presented as mean+/-SEM. The level of NO in exhaled air was higher in patients with active TB (16.2+/-1.2 parts per billion (ppb)) compared to control subjects (6.5+/-0.9 ppb), p<0.0001. Exhaled NO decreased with anti-TB treatment. Compared to control subjects (29.0+/-4.5 fluorescence intensity (FI)), iNOS expression on AM was upregulated in TB patients (86.3+/-12.5 FI) p<0.001 and the capacity for spontaneous generation of nitrite was enhanced. Nitrite production was inhibited by N(G)-monomethyl-L-arginine (L-NMMA), a competitive inhibitor of iNOS. The expression of iNOS on AM was related to the concentration of exhaled NO (r=0.66, p<0.001) and the nitrite generation capacity of AM (r(s)=0.77, p<0.001). We conclude that the increase in exhaled nitric oxide observed in patients with active pulmonary tuberculosis is due to an upregulation of inhaled NO synthase expression in alveolar macrophages which have an enhanced capacity for nitric oxide production.

Increased level of exhaled nitric oxide and up-regulation of inducible nitric oxide synthase in patients with primary lung cancer.

Monocyte-macrophage series have an important role in host surveillance against cancer. The cytotoxic/cytostatic activity of macrophages is, to a great extent, attributed to the up-regulation of inducible nitric oxide synthase (iNOS) and production of nitric oxide (NO). Here, in 28 patients with primary lung cancer and 20 control subjects, we measured the concentration of exhaled NO and nitrite in epithelial lining fluid (ELF) using a chemiluminescence NO analyser, and studied NOS expression in alveolar macrophages (AM) and lung tissues by flow cytometry; immunohistochemical analysis was also undertaken. The mean fluorescence intensity (FI) of iNOS expression in AM was significantly increased in patients with lung cancer (tumour side 263.5 +/- 15.2 FI, normal side 232.4 +/- 18.6 FI; n = 28) compared with that in control subjects (27.3 +/- 3.2 FI; n = 20, P< 0.001). The level of exhaled NO from cancer patients (16.9 +/- 0.9 p.p.b.; n = 28) was significantly higher than that in the control group (6.0 +/- 0.5 p.p.b.; n = 20, P < 0.001). The level of nitrite was also significantly higher in ELF from cancer patients (tumour side 271.1 +/- 28.9 nM and normal side 257.4 +/- 19.6 nM vs control subjects 32.9 +/- 4.1 nM; P< 0.001). The intensity of iNOS expression in AM was correlated with the level of exhaled NO (rs = 0.73, n = 76, P< 0.001) and the nitrite released in ELF (rs = 0.56, n = 76, P< 0.001). The nitrite generation of cultured AM from patients with lung cancer was significantly enhanced compared with that of control subjects after culture for 24 h (tumour side 5.75 +/- 0.69 and normal side 5.68 +/- 0.58 microM per 106 cells vs control group 38.3 +/- 3.6 nM per 106 cells; P< 0.001). The distribution of iNOS was identified in AM, tumour-associated macrophages, endothelium, chondrocytes, airway epithelium of both lungs and malignant cells (adenocarcinoma and alveolar cell carcinoma) of cancer patients. cNOS was labelled in alveolar macrophages, endothelial cells and nerve elements from lung tissue. Our results indicate that, in patients with primary lung cancer, the production of NO from alveolar macrophages was increased as a result of the up-regulation of iNOS activity. The increased NO production was not specific to the tumour side and might be attributed to the tumour-associated non-specific immunological and inflammatory processes of the host.

Efficacy of a cell phone-based exercise programme for COPD

The application of a supervised endurance exercise training programme in a home setting offering convenience and prolonged effects is a challenge. In total, 48 patients were initially assessed by the incremental shuttle walk test (ISWT), spirometry and the Short Form-12 (SF-12) quality-of-life questionnaire, and then every 4 weeks for 3 months thereafter and again after 1 yr. During the first 3 months, 24 patients in the cell phone group were asked to perform daily endurance walking at 80% of their maximal capacity by following the tempo of music from a program installed on a cell phone. The level of endurance walking at home was readjusted monthly according to the result of ISWT. In the control group, 24 patients received the same protocol and were verbally asked to take daily walking exercise at home. Patients in the cell phone group significantly improved their ISWT distance and duration of endurance walking after 8 weeks. The improvements in ISWT distance, inspiratory capacity and SF-12 scoring at 12 weeks persisted until the end of the study, with less acute exacerbations and hospitalisations. In the present pilot study, the cell phone-based system provides an efficient, home endurance exercise training programme with good compliance and clinical outcomes in patients with moderate-to-severe chronic obstructive pulmonary disease.

Relation of bronchoalveolar lavage T lymphocyte subpopulations to rate of regression of active pulmonary tuberculosis.

BACKGROUND--Effective host defence against mycobacterial infection chiefly depends on the interactions between macrophages and T lymphocytes. This study investigated the relation of cellular components and their activity of cells obtained by bronchoalveolar lavage (BAL) from the lower respiratory tract to disease regression in patients with active pulmonary tuberculosis without HIV infection. METHODS--Clinical indices including age, sex, the presence of diabetes, fever, the presence of resistant strains of mycobacteria, the bacterial load in sputum, and disease extent on chest radiography at presentation were assessed before commencing four-drug antituberculous therapy. Twenty two patients with active pulmonary tuberculosis were divided into rapid, intermediate, and slow regression groups. Subpopulations of alveolar macrophages separated using discontinuous Percoll density gradient centrifugation and T lymphocytes (with CD3, CD4, CD8, and CD25 monoclonal antibodies) were quantified. RESULTS--There were no differences among rapid, intermediate, and slow regression groups in terms of age, sex, the presence of diabetes, the presence of resistant strains of mycobacteria, or the bacterial load in sputum. No differences were found between the groups in terms of subpopulations of alveolar macrophages or numbers of CD3 and CD4 lymphocytes. By contrast, an increase in CD8 cells was shown in the slow regression group compared with the rapid and intermediate regression groups. CD25 cell numbers were increased in the rapid regression group compared with the slow regression group. The CD4/CD8 ratio was decreased in the slow regression group compared with the rapid and intermediate regression groups and the relation between the proportion of CD25 cells and the CD4/CD8 ratio in BAL fluid was significant. CONCLUSIONS--A decreased CD4/CD8 ratio with an increase in CD8 cells in the alveolar spaces was associated with slow disease regression in patients with active pulmonary tuberculosis without HIV infection, suggesting that the balance of T lymphocyte subsets may play a central part in the modulation of host defence against mycobacterial infection.

Regional Amyloid Deposition in Amnestic Mild Cognitive Impairment and Alzheimer's Disease Evaluated by [18F]AV-45 Positron Emission Tomography in Chinese Population

Background To compare the neocortical amyloid loads among cognitively normal (CN), amnestic mild cognitive impairment (aMCI), and Alzheimers disease (AD) subjects with [18F]AV-45 positron emission tomography (PET). Materials and Methods [18F]AV-45 PET was performed in 11 CN, 13 aMCI, and 12 AD subjects to compare the cerebral cortex-to-whole cerebellum standard uptake value ratios (SUVRs) of global and individual volumes of interest (VOIs) cerebral cortex. The correlation between global cortical [18F]AV-45 SUVRs and Mini-Mental State Examination (MMSE) scores was analyzed. Results The global cortical [18F]AV-45 SUVRs were significantly different among the CN (1.08±0.08), aMCI (1.27±0.06), and AD groups (1.34±0.13) (p = 0.0003) with amyloidosis positivity rates of 9%, 62%, and 92% in the three groups respectively. Compared to CN subjects, AD subjects had higher SUVRs in the global cortical, precuneus, frontal, parietal, occipital, temporal, and posterior cingulate areas; while aMCI subjects had higher values in the global cortical, precuneus, frontal, occipital and posterior cingulate areas. There were negative correlations of MMSE scores with SUVRs in the global cortical, precuneus, frontal, parietal, occipital, temporal, posterior cingulate and anterior cingulate areas on a combined subject pool of the three groups after age and education attainment adjustment. Conclusions Amyloid deposition occurs relatively early in precuneus, frontal and posterior cingulate in aMCI subjects. Higher [18F]AV-45 accumulation is present in parietal, occipital and temporal gyri in AD subjects compared to the aMCI group. Significant correlation between MMSE scores and [18F]AV-45 SUVRs can be observed among CN, aMCI and AD subjects.

Electrophysiological features of Hirayama disease.

Introduction: The purpose of this study was to compare the pattern of hand muscle involvement in Hirayama disease (HD) and amyotrophic lateral sclerosis (ALS). Methods: We reviewed findings of upper limb nerve conduction studies of 46 HD patients and 60 ALS patients. The findings from 54 healthy subjects were used for comparison. Results: In HD, the ulnar compound muscle action potential (CMAP) amplitude was more severely reduced than the median one, and the reverse pattern was observed in ALS. The mean ulnar/median (U/M) CMAP amplitude ratio was significantly lower in HD (0.64 ± 0.79) and abnormally higher in ALS (2.15 ± 1.77) compared with normal subjects (0.89 ± 0.23). An abnormally low U/M CMAP amplitude ratio (<0.6) was encountered in 34 patients with HD and in 1 with ALS. A U/M CMAP amplitude ratio ≥4.5 or absent median motor response was found only in ALS. Conclusion: Our findings demonstrate different patterns of hand muscle involvement between these two diseases. Muscle Nerve, 2011

Rapid progression and brain atrophy in anti-AMPA receptor encephalitis

Anti-α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptor encephalitis is an anti-neuronal surface antigen autoimmune encephalitis that is rarely reported. Our study evaluated the first known patient who developed anti-AMPA receptor encephalitis during pregnancy. Initial brain MRI revealed bilateral limbic encephalitis. However, rapid brain atrophy on MRI with extensive hypometabolism of cerebral cortices, caudate nuclei and brain stem hypoperfusion on (18)F-FDG PET developed when clinically progressed. IgG index of serial CSF studies reflected the clinical improvements after plasmapheresis and plasma exchange. The clinical spectrum of anti-AMPA receptor encephalitis may be expanded from limited limbic involvement to extended central nervous system.

Features of varicella zoster virus myelitis and dependence on immune status.

BACKGROUND Myelitis is a rare complication of varicella zoster virus (VZV) infection and is more prevalent in immunocompromised individuals. Clinical features, outcomes, and presentations vary. The aim of the current study was to compare the clinical presentations of our patients with those reported in the literature, and to evaluate the differences in clinical features between immunocompromised and immunocompetent patients. METHODS A review of the literature on VZV myelitis was carried out by searching PUBMED from 1980 to 2012. Clinical features of our cases and those in the literature were compared. RESULTS There were 5 cases at our hospital and 26 were reported in the literature. Seventeen patients were immunocompromised (54.8%), and most had acquired immune deficiency syndrome (AIDS). Typical presentations (skin lesions followed by myelopathy at the corresponding level) were observed in 14 patients (45.2%). The immunocompromised patients were prone to atypical presentations (p<0.05). Outcomes were good in immunocompetent patients and relatively poor in immunocompromised patients (p<0.05). Anti-herpetic agents had no statistically significant effect on outcomes in immunocompromised patients (p=0.280), but could reduce mortality rate in AIDS patients (p<0.05). CONCLUSION Immunocompromised individuals are susceptible to this disease, and prone to atypical presentations and poorer outcomes. Timely recognition and anti-herpes therapy may be beneficial to the outcomes. In the AIDS patients, anti-herpes therapy can reduce mortality effectively.

Effect of endogenous nitric oxide on tumour necrosis factor-α-induced leukosequestration and IL-8 release in guinea-pigs airways in vivo

1 Tumour necrosis factor‐α (TNF‐α) is implicated in the pathogenesis of many pulmonary and airway diseases. TNF‐α stimulation may release interleukin‐8 (IL‐8) in airways mediated via an increase in intracellular oxidant stress. In the present study, we have assessed leukosequestration and IL‐8 release in the airways in response to intratracheal administration of human recombinant TNF‐α, and examined the modulatory role of endogenous NO by pretreatment with a NO synthase inhibitor Nω‐nitro‐L‐arginine methyl ester (L‐NAME). 2 TNF‐α (102–104 u) was administered intratracheally in male guinea‐pigs which were anaesthetized with urethane and were ventilated artificially. TNF‐α induced a time‐ and dose‐related increase in neutrophil numbers and a concomitant increase in human IL‐8 equivalent level retrieved from bronchoalveolar lavage (BAL) with the peak effect at 103 u at 6 h of TNF‐α injection (late phase). Intratracheal administration of recombinant human (rh)IL‐8 (0.025, 0.25, 2.5 ng) producing a similar range of human IL‐8 equivalent levels in BAL as measured in our results induced neutrophil recovery in BAL fluid to a similar extent. Administration of anti‐IL‐8 antibody prevented the late phase of neutrophil recruitment induced by TNF‐α or rhIL‐8. 3 Pretreatment with L‐NAME significantly enhanced the TNF‐α (103 u)‐induced neutrophil recruitment and human IL‐8 equivalents production at 6 h, but not at 1 h of TNF‐α administration (early phase). L‐Arginine reversed the responses to L‐NAME. Pretreatment with 0.2% DMSO (i.v.) significantly inhibited TNF‐α‐induced neutrophil recruitment and human IL‐8 equivalents release both in the early and late phase of the responses. Pretreatment with DMSO also inhibited the enhancement effect of L‐NAME on the late phase of TNF‐α‐induced responses. DMSO failed to modify exogenous rhIL‐8‐induced neutrophil recruitment. Neither L‐NAME nor DMSO alone induced any significant change in neutrophil numbers or human IL‐8 equivalent level in BAL fluid. 4 Neutrophil depletion by cyclophosphamide pretreatment failed to modify TNF‐α‐induced human IL‐8 equivalent release. 5 The expression of β2‐integrin, CD11b/CD18 on neutrophils was increased only in the late but not early phase of TNF‐α stimulation. L‐NAME failed to modify these responses. 6 In conclusion, we demonstrated that NO may be an important endogenous inhibitor of TNF‐α‐induced leukocyte chemotaxis via inhibition of IL‐8 production. Thus, the production of NO in airway inflammatory diseases may play a negative feedback role in self‐limiting the magnitude of inflammatory responses.

Neurological Complications of Acute Intermittent Porphyria

Background: Acute intermittent porphyria (AIP) is an inherited disorder of heme biosynthesis, the clinical manifestations of which are incompletely understood. In this report, we describe 12 cases of AIP, focusing on the neurological manifestations. Methods: Twelve patients were diagnosed with AIP on the basis of characteristic clinical findings, erythrocyte porphobilinogen deaminase (PBGD) activity, and molecular genetics. Central and peripheral nervous system manifestations were noted, and electrophysiological and radiological studies performed. Potential precipitating factors were recorded. Results: Eleven PBGD gene mutations were identified in 12 patients. Nine patients experienced neurological symptoms involving the central nervous system (consciousness disturbance, n = 8; convulsion/seizure, n = 4; behavior change, n = 1), while 7 patients experienced peripheral neuropathies (motor paresis, n = 7; impairment of bulbar or respiratory function, n = 4). The electrophysiological and electroencephalographic findings were consistent with the neurological symptoms of AIP. Urinary PBG and δ-aminolevulinic acid levels were elevated in all patients. PBGD enzyme activity levels were below normal in all patients. Eight patients had documented exposure to porphyrogenic agents. Conclusions: Our detailed description of a relatively large number of cases of AIP may help clinicians to recognize this often difficult-to-diagnose disorder.